1. Field of the Invention
The invention relates in general to the field of data entry interfaces, such as keyboards and the like, and more particularly to a modified QWERTY letter layout that is especially useful for the rapid entry of data into hand-held electronic devices (such as a cellular phone or personal digital assistant).
2. Description of the Related Art
The first typewriter worked with three or four rows of finger-tip size buttons called “keys.” Each key could be depressed by the outstretched fingers of the hands of the typist as the entire layout of keys was designed to be approximately the width of two hands. From this simple beginning, the typewriter has given rise to a plethora of data entry interfaces based on the underlying concept of the tactile input of text-based information. Indeed, everyone who has used a typewriter or computer in the last ten years is familiar with data entry interfaces known simply as “keyboards”, “keypads,” or even “touch screens.”
Keyboards and keypads are still the preferred means for entering information into devices such as hand-held electronic devices, computers, and cell phones. Normally, keyboards include the ability to enter numbers, alphabetic characters, punctuation, and control characters. At least for the English language (and others utilizing the 26 characters of the Roman alphabet), the ubiquitous “QWERTY” keyboard arrangement has become the de-facto standard layout of letter characters, numbers, and punctuation. An illustration of the standard QWERTY keyboard layout is shown in FIG. 1.
The QWERTY keyboard has three rows of letter keys and one row of number keys with approximately 12 keys per row. The top row of a QWERTY keyboard usually contains the numbers, along with various symbols and punctuation marks. The bottom three rows contain all of the letter characters and some additional punctuation marks. The 4 rows of keys with 12 keys per row cause the keyboard to be substantially wider than it is tall. Thus, the main problem with this keyboard design is that it is relatively large, making it unsuitable for hand-held portable devices and other applications where size and the dimensions of the data entry interface are constraints.
In other words, the traditional QWERTY layout does not work well in applications where it would be desirable to have a keyboard that is taller than it is wide, such as a cell phone keypad. In fact, previous QWERTY-type keyboards are either so large that they are difficult to manually operate with one hand (and add too much bulk to a small electronic item) or so small that the size of the keys are reduced to the point where the use of a “stylus” (a thin, often plastic “stick” used for pressing the buttons) becomes necessary to avoid mashing several keys at once with one's fingers.
While several inventions have attempted to modify the QWERTY layout of keys to suit a particular purpose, none are known to overcome all of the aforementioned problems. For example, U.S. Pat. No. 6,445,380 issued to Klien discloses a variation on a standard QWERTY layout, but retains the typical 3 row arrangement of letters. Similarly, U.S. Pat. No. 5,626,429 issued to Choate suggests the possibility of increasing the number of QWERTY keyboard rows to 4 or more, but with the requirement that there be at least nine “columns” or keys in a row. Other inventors, such as Ichbiah in U.S. Pat. No. 5,487,616, abandon the QWERTY layout altogether in favor of a keyboard arrangement based on the frequency of use for each character.
Recent experience has shown that when designers have attempted to design small keyboards that are taller than they are wide, they have typically abandoned the QWERTY layout and used character arrangements based upon alphabetic ordering. Examples of alphabetically ordered keyboards of the prior art are shown in FIGS. 2-4. The main problem with these designs is that it takes users longer to visually acquire their desired target character on the keyboard because they must scan the alphabet until a letter is located. Especially for anyone who has been trained to type on a QWERTY keyboard, the visual acquisition process markedly slows down the rate of text input.
Similar alphabetically ordered layouts have been designed for cell phone keypads (see FIG. 5). The main problem with these layouts is that telephone keypads are primarily designed to enter the digits 0-9 and the characters # and *. The ability to enter the letters A-Z, punctuation and control characters has not been a priority, as demonstrated by the existence of keypads that make it particularly labor-intensive to enter text. For example, one common telephone keypad design (FIG. 5) requires the user to hit a particular key from 1 to 5 times to differentiate between (and thereby enter) just a single character or number.
Another keyboard design, known by the trademark FASTAP, is arranged much like as in FIG. 4. The main problem with this design is that it uses a substantially alphabetic ordering of letters A-Z (and the resultant slowing of data entry, especially with users who are familiar with a QWERTY keyboard layout). Another problem with this design is that by using only four characters per row, direct access to the alphabet and a limited number of non-alphabet characters must be squeezed into seven rows of buttons. Because of space constraints, other characters or punctuation marks must be “scrolled through” on the screen one at a time and selected.
In view of the above, it would be desirable to have a data entry interface that could be taller than wide, would fit within the dimensions of existing hand-held electronic devices, and allow for faster data entry than previous designs.